First British offensive to regain land lost to the Japanese in Burma. In January 1942, Japanese forces drove into Burma (Myanmar) from Thailand to sever Allied lines of communication into China, gain a dominant position in Southeast Asia, and threaten British India. By May, British forces—along with allied Indian, Burmese, and Chinese units—were being pushed north and east into China and north and west into India. In June, the British-controlled forces were holding along the Indian border forward of Ledo, Imphal, and Chittagong, where they began to rebuild and refit their battered forces. In July, commander of the British Eastern Army Lieutenant General N. M. Irwin began planning for an offensive operation against Arakan, a northwest coastal province of Burma bordering southwestern India (now Bangladesh) and separated from the rest of Burma by mountainous jungle terrain.

The offensive was to begin in the late fall and was designed to clear elements of Japanese Lieutenant General Takeuchi Hiroshi's 55th Division from the Mayu Peninsula and Akyab Island. In December, Major General W. L. Lloyd's 14th Indian Division conducted a two-pronged assault down the peninsula. Initially successful, the British were in striking distance of Akyab when General Iida Shojiro, commander of the Japanese Fifteenth Army, reinforced and strengthened the defensive positions near Donbaik and Rathedaung. The British then reinforced the stalled 15th Indian Division with five additional infantry brigades and a troop of tanks. The March 1943 assault on Donbaik failed, and the Japanese quickly then began a counteroffensive that drove Japanese forces back up the peninsula. The 55th Division struck from Akyab, while other Japanese units worked their way over the supposedly impassable mountains to hit the British left flank and rear areas during 13–17 March.

In early April, Major General C. E. N. Lomax relieved Lloyd with the mission of stemming the Japanese attack. British Lieutenant General William Slim, commander of XV Corps, and his staff were redeployed from Ranchi to Chittagong, although Slim did not receive command of the operation until mid-April. The 26th Division headquarters deployed to relieve the staff of the 14th Division when ordered. Fighting on the Mayu Peninsula raged as Japanese units took full advantage of their proven jungle warfare tactics to outmaneuver and cut off British units at multiple points. Lomax attempted to entrap the rapidly advancing Japanese forces; however, although his plan was sound, the battle-weary British forces were overcome and were again forced to retreat, having suffered significant losses of transport and equipment. The Japanese reoccupied Arakan on 12 May. British forces were finally able to disengage and establish a stable defensive position near Cox's Bazaar. The first campaign for the Arakan area was over; the British offensive to regain Burmese territory had failed, and the reputation of Japanese forces as unmatched jungle fighters continued to grow.